replacing rear ?
For a simple cruiser you can also look for open diffs which are super common and dirt cheap
Updating the speedo with a tuner covers the base for different gearing. Only other thing to look for is 3 channel vs 4 channel to keep your ABS/traction control working
3 channel has the sensor in the top of the diff housing, 4 channel has one sensor behind each wheel
Dont be afraid of earlier LT1 axles either. Swap your old brakes over and they're the same. 3rd gen axles have a different backspacing so avoid them unless you want to run spacers. Avoid drum axles unless you are fine with cutting/drilling. Disk brakes wont simply bolt up, but can be made to work
If you're fairly knowledgeable with a wrench and can muscle about 100lbs around, then an axle swap wont be any trouble. For your first time expect about 5 hours to get it done


